Information About ISSU

In a Nexus 7000 series chassis with dual supervisors, you can use the in-service software upgrade (ISSU) feature to upgrade the system software while the system continues to forward traffic. An ISSU uses the existing features of nonstop forwarding (NSF) with stateful switchover (SSO) to perform the software upgrade with no system downtime.

An ISSU is initiated through the command-line interface (CLI) by an administrator. When initiated, an ISSU updates (as needed) the following components on the system:

Supervisor BIOS, kickstart image, and system image

Module BIOS and image

Connectivity Management Processor (CMP) BIOS and image

CMP is a Supervisor 1 only feature.

In a redundant system with two supervisors, one of the supervisors is active while the other operates in the standby mode. During an ISSU, the new software is loaded onto the standby supervisor while the active supervisor continues to operate using the old software. As part of the upgrade, a switchover occurs between the active and standby supervisors, and the standby supervisor becomes active and begins running the new software. After the switchover, the new software is loaded onto the (formerly active) standby supervisor.

Virtualization Support

An ISSU-based upgrade is a system-wide upgrade that applies the same image and versions across the entire system, including all configured virtual device contexts (VDCs). VDCs are primarily a control-plane and user-interface virtualization and cannot run independent image versions per virtualized resource.

RFCs

RFCs

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No RFCs are supported by this feature

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